Hello and welcome, katycomputersystems !
I want to just briefly detail the differences between the two services for those who may not know. T-Mobile was really aiming to solve the problem of spam callers with these two features, and I see them as two different approaches to a problem. If you're not interested in the descriptions, please skip to the last paragraph.
Scam ID is basically the older "security alarm" of the T-Mobile arsenal against spammers. It basically checks the Caller ID/Phone # against a database of known/suspected spammers and if it comes back as a match- it replaces the Caller ID on your phone with "Scam Likely". It tells you there might be a spammer on the other line, but doesn't actively do anything to prevent the conversation from happening. Due to the database also having suspected spammers included, you may observe some local businesses labeled as a scam (which you can report as a false positive.) This is also provided as a free service to pretty much all T-Mobile consumer lines.
Scam Block is the "security system" available to you to use. If and when the incoming caller is identified as a spammer using the tools I previously outlined, the network blocks the call from ever being received by your phone. In this way, it acts as a defense to these frequent calls. This may cause problems if your local business uses a number that was previously identified as a Spam Caller. Also provided free of charge.
If you are using Scam Block, the caller will not be routed through completely. I don't think the Spammer would be forwarded to voicemail or anything, the call would just disconnect- that could be an indication that the number has been blocked. If you're using Scam ID, you'll have the opportunity to answer the call regardless and be the judge yourself. Which, may be even more advantageous to some than Scam Block.
What is best way to post feature requests?
It would be lovely if after a voice call, the phone would check to see if the caller is in my phone book. If not, it would ask me if this was a scam call, that would help us help TMO. I do use T-Mobile Scam Call Reporting but it would be nice to be able to enter these irritating calls as they come in.
If there were some easy way to press a button on the call log that a particular number was a spam, I would do it. I'm not going to take the time to log on to a website to simply type in a particular spam number. I have programmed my phone to show that a call coming in is likely to be spam. I may change that to simply block spam calls. I wanted to see how accurate this feature was before doing.